Lumber separator



p 1963 s. L. LUNDEN ETAL 3,104,005

LUMBER SEPARATOR Filed 0ot. 20, 1961 4 -Sheet 2 Q d X a Q Q" g o I II IIINVENTORS Sidney L. Lunden DonaLd E. Mosely BY %J&

Attys.

Sept. 17, 1963 s. L. LUNDEN ETAL 3,

LUMBER SEPARATOR Filed Oct. 20.. lei 4 Sheets-Sheet 3 Sid/2e) L. LundenDonald E. Mosely IN V EN TORS Attys.

United States Patent 3,104,005 LUMBER SEPARATOR Sidney L. Lnnden andDonald E. Mosely, both of Spokane, Wash, assignors to Bitco, Inc,Spokane, Wash, a corporation of Idaho Filed Oct. 20, 1961, Ser. No.146,461 7 Claims. (Cl. 198-21) The present invention relates to a novelapparatus adapted to facilitate the separation of cut boards fromvertically stacked cants or boards requiring further processmg.

This invention is concerned with the separation of cut boards afterbeing formed in a lumber processing mill. The modern mill operationoften includes a horizontal resaw through which are fed the squared offcants or slabs which are to be cut into usable dimension lumber. Such ahorizontal resaw normally produces a cut board upon which is stacked theremainder of the cant or another board which may require futureprocessing. Normally such cut boards must be separated by manualprocedures which are both time consuming and expensive. For this reasonthe present invention contemplates a mechanical device which willautomatically separate the usable board from the remainder of the cantwhich must be further processed.

It is a first object of this invention to provide a lumber separatorwhich is capable of handling the output of a high speed horizontal resawassembly. In order to accomplish this purpose the present inventionutilizes both transverse and longitudinal movement of the board which isto be separated from the remaining portion of the cant.

It is another object of this invention to provide a lumber separator inwhich the movement of the boards themselves is utilized to effect thenecessary separation. This is accomplished by providing a fixed abutmentagainst which the moving board assembly must collide, thereby causing aportion of the assembly to stop, while allowing the remainder of theassembly to pass over the abutment. Thus no additional mechanicallinkages, pusher bars or other apparatus are necessary to complete thedesired separation of board and cant.

It is another object of this invention to provide suitable controlswhich are capable of activating the conveyor assemblies to complete theseparation steps. These con trols are activated by electrical componentsand are positioned so as to be actuated by the boards themselves at theproper time to maintain the necessary sequence of events leading to thefinal separation.

Another object of this invention is to provide controls and movablebulkheads so 'as to allow a manual operator to alternately preventseparation of the assembly when such separation is unnecessary. Thesecontrols will be utilized at the final working of a cant, should thelast board be an even thickness so as to produce two boards with thefinal sawing operation.

Another object of this invention is to provide movable cant controls sothat the remaining cant or boards may alternately be directed back tothe horizontal resaw operation, or may be directed to a chipper or otherwaste processing machine.

These and further objects will be evident from a study of the followingdisclosure taken in conjunction with the accompanying drawings to whichreferences will be made. The embodiment illustrated in the drawings isillustrative only and is not intended to limit or restrict the scope ofthe invention which is properly defined in the annexed claims.

In the drawings:

FIGURE 1 is a top view of the separator with the delivery conveyor andthe return conveyors broken away at the left hand side, the centralportion of the separator 7, 3 ,104,005 Patented Sept. 17, 1963 ice beingbroken away and the final conveyor table being broken away at the rightside of the figure;

FIGURE 2 is a side view of the assembly as seen in FIGURE 1;

FIGURE 3 is a sectional view taken along line 3-3 in FIGURE 1;

FIGURE 4 is an enlarged sectional view taken along line 44 in FIGURE 1,with the transverse conveyor shown in its lowered position;

FIGURE 5 is a view similar to FIGURE 4, but taken along line 5-5 inFIGURE 1, showing the conveyor in its raised position;

FIGURE 6 is taken along the same plane'as FIG URE 5, but extends fartherto the left and illustrates the separation of board and cant; i i

FIGURE 7 is an enlarged section view taken through line 77 in FIGURE 5;

FIGURE 8 is a sectional View of a portion of the side rail as seen alongline 88 in FIGURE 4;

FIGURE 9 is an enlarged sectional view taken along line 99 in FIGURE 8;and

FIGURE 10 is a circuit diagram of the electrical controls for a singleseparator assembly.

Modern lumber processing often includes a horizontal resaw mill in whichsquared off cants or slabs are cut horizontally into the desired roughboards of proper thickness. The horizontal resaw is basically a largeband saw with a horizontal cutting flight of saw teeth. The boards beingout are moved along a conveyor past the stationary saw. The producttherefore is a cut board upon which is stacked the remainder of thecant, or in the case of the final cut, a narrow strip of board orpossibly a second board of a desired thickness. The separation of thelower board from the remainder of the cant presents a problem since thisboard should be directed further to a planing mill edger or a dryingkiln, and the remainder of the cant must be directed back to thehorizontal resaw for further cutting operations. The apparatus to bedescribed below presents an automatic device for effecting thisseparation.

The separator is generally shown in FIGURES 1, 2 and 3. It consists of afixed framework 10 which shall include all the fixed supporting membersfor the various conveyors which will be described. The first element onthe framework 10 is a delivery conveyor 11. The con veyor 11 comprisesoutfeed rollers 12 which may be power driven by any suitable means (notshown). The outfeed rollers 12 of the delivery conveyor 11 carry theboards past the horizontal resaw during the cutting operation. Thatportion of the delivery conveyor illustrated in FIGURES 1-3 is thedelivery end thereof. The boards 9, shown in FIGURE 1, are moving in thedirection of arrows 9a.

The apparatus illustrated in the drawings is designed to service a pairof lumber lines emanating [from a horizontal resaw assembly. Thus theapparatus includes two duplicate devices which are mirror images of oneanother and which operate in precisely the same manner. A divider 19separates the two devices along the center line of table 13. Thus twoboards 9 are illustrated at the left hand side of the figure and will beprocessed entirely independently of one another. For purposes ofdescription only a single device will be referred to, although it mustbe kept in mind that identical numbers will distinguish identicalcorresponding parts of 'both devices. The two separators may obviouslybe used as shown in FIGURE 1, or may be divided so as to eliminate onedevice where a single lumber line is being processed.

The second basic element in the separator is a receiving table 13. Thetable 13 is supported basically between a pair of longitudinal sidechannels 14 which const-itute a fixed part of the framework Ill.Intermediate longitudinal channels 14a are also provided for foundationpurposes. The channels 14 and 14a support cross channels 15 whichinterlock between the two separating devices. The cross channels 15along each device constitute a pair of outwardly facing channels havinga space between their vertical webs. Mounted on the framework are upperplates 17 whichconstitute the supporting elements of the receiving table13. The plates 17 are rigidly fixed to the framework 10 by means ofsupporting brackets 18. It is to be noticed from FIGURE 3 that the righthand end of each plate 17 is elevated above its left hand end. Thisslight rippling effect along the table 13 is designed to protect thelateral conveyors 20- which are located within the spaces bounded by theoutwardly facing channels 15. Thus as boards 9 are pushed onto thereceiving table 13 by the action of rollers 12, the leading ends of theboards 9 will strike the upper surfaces of the plates 17 and will boundacross the open areas in which are located the cross channels 15.

Up to this point it may be understood that the boards 9 are fed from theroller 12 onto the plates '17. It is important to note that the rollers12 are elevated slightly above the upper surfaces of plates 17 so thatthe rear end of each board 9 remains in an elevated position and bridgesslightly over the left hand end of the receiving table 13. By thisaction the boards 9 will be pushed along the receiving table 13 untilthe boards 9 rest entirely on the plates 17.

Directly below the paths of the boards 9 are a plurality of lateralconveyors 20. Each conveyor 20 is directed perpendicularly to theposition of the boards 9 on the plates 17. Each lateral conveyor isidentical in structure and can best be seen in the enlargedillustrations of FIG- URES 4 through 7. The conveyor includes an inboardidler sprocket 21 and an outboard sprocket 22. The outboard sprocket 22is adapted to be driven through a common shaft 19. The two sprockets 21and 22 are enmeshed with a chain 23 which is loosely wrapped about themto form a continuous loop. The chain 23 is a common sprocket chain andhas smooth links which are capable of supporting articles placedthereon.

The chain 23has an upper flight which extends across the paths of themoving boards 9. This upper flight is mounted within a chain supportframe24 The support frame 24 is basically an upwardly facing channelalong which the chain is slidably carried. The support frame 24 isvertically movable and is mounted on the framework 10 by means of anidler link 25 and a bell crank 26 which cooperate to form aparallelogram support linkage. The bell crank 26 is adapted to be movedfrom the position shown in FIGURE 4 to the position illustrated inFIGURE 5, by means of a movable cylinder assembly 28. The bell crank 26of the various aligned conveyors 20 is operated by means of a commonoperating shaft 26a.

At the outboard end of each lateral conveyor 20 and adjacent thesprockets 22 is a longitudinal abutment 30 which is the vertical web ofthe side channel 14. This abutment 30 is placed along the outboard endsof the conveyors 20 and is mounted adjacent a row of rollers 31. Therollers 31 constitute a conveyor assembly along which the lower board iscarried parallel to the length of the moving boards 9 being delivered bythe delivery conveyor 11.

The basic operation of these elements is quite simple. The supportingframe 24, below each chain 23, is moved in unison with each of the otheraligned chains 23 by means of the cylinder assembly 28. Each chain 23 ismovable from a first position illustrated in FIGURE 4, wherein the topchain surface is slightly below the upper surface of the adjacent plate17, to a second position illustrated in FIGURE 5, wherein the topsurface of the chain 23 is slightly above the adjacent upper surface ofthe plate 17. Thus the chain 23 in each lateral conveyor 20, canalternately clear the moving boards 9 as they are .4 received on thetable 13, or lift the boards 9 from the plates 17. The outboardsprockets 22 are rotated in the direction of the arrow illustrated inFIGURE 5. Thus after a board has been fully received on the table 13, itmay be lifted by means of the cylinder assembly 28 and frame 24 so thatthe boards 9 rest only on the moving chains 23. The chains 23 thus carrythe boards 9 laterally, as seen in FIGURE 5. The laterally moving boardsare then deposited on the rollers 31 and will continue to slide untilthe lower board strikes the raised abutment 30. The speed of the chains23 is very rapid and results in a high momentum of the moving boards 9as they strike the abutment 30. The tangential upper surfaces of therollers 31 is located intermediate the two positions of the top surfacesof the chains 23, supported by frames 24. The elevation of the abutment30 above the second position of the chain 23 is less than the thicknessof the lower board 9, which is to be separated from the remaining cant.Thus the remainder of the cant will fiy over the raised abutment 3t andthe cut board 9 will remain on the rollers 31. The rollers 31 may bedriven by any common drive mechanism so as to propel the separatedboards 9 parallel to the abutment 30.

The disposal of the cants 9 requires two separate procedures. During theinitial cutting of the cant 9 the remainder of the can should bedirected back to the resaw operation for further cutting. In order toeffect such motion, a movable gate 32 is provided adjacent each sidechannel 14. The gate 32 is normally inclined in the position illustratedin full line in FIGURE 6 and shown in FIGURES 1 and 2. The dump gate 32is pivotally mounted at its lower end as shown at 32a in FIGURE 6. Thispivotal mounting 32a is a direct connection to the basic framework 10.Directly to the left of the gate 32, as seen in FIGURE 6, is a returnconveyor 33. The return conveyor 33 is a conventionally powered rollerconveyor which will effect motion of the cant in a direction opposite tothe motion of the boards 9 as they are delivered from the deliveryconveyor 11. Within the space between the return conveyor 33 and thevertical frame member 57 is a waste conveyor 34. The conveyor 34 isnormally covered by the gate 32 so that the slabs will ride from theinclined gate 32 and be deposited on the return conveyor 33. The wasteconveyor 34 is properly connected to a conveyor system leading to achipper apparatus or other waste disposal means. Where a cant has beensawed to a point where the remainder of the cant is unusable, thisremainder will be deposited on the waste conveyor by rotation of theconveyor gate 32 to the dashed line position illustrated in FIGURE 6.Thus cants riding over the abutment will fall between the gate 32 andthe vertical post 57 and be directly deposited on the waste conveyor 34.

In normal sawing operation, it is also possible to complete the sawingof the cant with two boards of the desired thickness being one on top ofthe other. In other words, the sawing operation results in the evencutting of the desired boards. When this occurs, both boards should bedirected along the rollers 31 adjacent to the raised abutment 30. Inorder to effect this action the mechanism illustrated in FIGURES 8 and 9has been included in the present apparatus. This mechanism includesmovable stop arms 35 which are pivotally mounted along the abutment 30.The normal position of stop arms 35 is fiush with the surfaces of theside channels 14. Each arm constitutes a bell crank which is pivoted at36. The arms 35 are movable to an upraised position illustrated indashed lines in FIGURE 8, where the arms 35 will block movement of theupper board over the abutment 30. The arms 35 are adapted to be actuatedby means of a common connecting linkage 37.

Both the gate 32 and the arms 35 are actuated by suitable cylinderassemblies. The gate 32 is adapted to be moved upwardly by a doubleacting cylinder assembly 29. Assembly 29 rests at the positionillustrated in FIG- URE 6. The arms 35 are adapted to be moved to theupper position illustrated in dashed lines in FIGURE 8 through theconnecting linkage 37 by means of a common double acting cylinderassembly 38. The cylinder assembly 38 rests in the full line positionillustrated in FIGURE 8.

The basic object of this invention is to provide a completely automaticseparating assembly which is subject to manual alternate controls. Inorder to provide a machine which is automatic in operation the boards 9must themselves control the raising and lowering of the chains 23. Thisis accomplished first by means of a hinged plate 40 at the end of thereceiving table 13 adjacent the delivery conveyor 11. Each hinged plate40 lies directly below the paths of the boards9 as they are fed from thedelivery conveyor 11. Each plate 40 is independently mounted on aframework 10 by means of a hinge 41. A limit switch 42 is provided beloweach plate 40 and biases the end of the plate 40 opposite to the hinge41 to a position slightly elevated above'the upper surfaces of theplates 17. Due to the elevation of the roller 12 above the plates 17,the hinged plate 46 below each board will not be engaged by the movingboard until the rear end of the board has cleared the last roller 12. Atthis time the board will fall upon the plate 40, causing the plate topivot downwardly and thereby actuate the switch 42. The second controlalong the receiving table 13 is a simple limit switch 43 which ismounted between the supporting portions of the side rollers 31. Theswitch 43 is mounted on the framework 10 and is adapted to be contactedby the leading edge of the moving boards 9 as they are carried along thechains 23.

The operation of these switches from a mechanical standpoint is believedto be clear from this description. The circuit in which the switches isutilized is illustrated in FIGURE 10. Besides the switches 42 and 43,there is also provided a manual switch 44 adapted to control the movablegate 32, and a second manual switch 45 adapted to control the arms 35.The switch 42 is normally open, while the switch 43 is normally closed.Both manual switches 44 and 45 are normally open and are preferably ofthe push button type which is momentarily closed by contact of a personsfinger.

Power for the control circuit is provided by two lines 46 and 47 whichare wired to a suitable power source (not shown). The circuit forcontrol of the chains 23 is a direct series connection of switches 42and 43 with a solenoid 55 which, when actuated, operates a valve tosupply pressure to the cylinder assembly 28 to thereby raise the chainsupport frames 24. Thus, when a board contacts the switch 42, thecircuit to solenoid 55 is completed, and the chains 23 are raised to theposition illustrated in FIGURE 5, to thereby carry the boards 9 acrossthe receiving table 13. When the boards have been carried into contactwith the limit switch 43, the circuit to the solenoid 55 will be openedand the pressure to cylinder assembly 28 will be reversed to therebyreturn it to its initial position.

The remainder of the circuitry illustrated in FIGURE 10 is provided toautomatically operate the gate 32 and arms 35 at the proper times whensuch operation is desired. In order to effect such operation, theoperator of the machine must merely close the respective switch 44 or 45at some time during the cycle. Each switch 44 and 45 is wired in aparallel circuit, as can be seen in FIGURE 10. The first switch 44,which operates the gate 32, is wired in series across the lines 46 and47 with a relay 48 and contacts 51a of a time delay relay 51. The relay48 is provided with three sets of contacts 48a, 48b and 480. The firstset of contacts 48a are wired across the terminals of the switch 44 andhold the relay 48 in its activated relationship after closing of theswitch 44. The second set of contacts 48!) are wired in series with asolenoid 50 which, when activated, operates a valve to direct pressureto the cylinder assembly 29 to thereby 6 move the gate 32 to theposition shown in dashed lines in FIGURE 6. The third contacts 480 areconnected to the line 46. The manual switch 45 is wired in a similarcircuit shown in FIGURE 10. Switch 45 is wired in series with a relay 52and the contacts 51a across the lines 46 and 47. Relay 52 is alsoprovided with three sets of contacts 52a, 52b and 520. The first set ofcontacts 52a is wired across the terminals of the switch 45 and operatesto hold the relay 52 in its activated condition. The second set ofcontacts 52b is wired in series with a solenoid 53 which operates avalve to direct pres sure to the cylinder assembly 38 to thereby movethe arms 35 to their raised positions illustrated in dashed lines inFIGURE 8. The third set of contacts 520 is connected to the line 46 andare Wired in parallel with the contacts 430. As may be seen in FIGURE10, both relays 48 and 52 are provided with parallel contacts 48b and52b and 480 and 520. These parallel contacts are connected respectivelyto lines 58 and 59.

Wired in parallel with the solenoid 55 is a relay 54. Relay 54 istherefore connected in series with the switches 42 and 43 across thelines 46 and 47. The relay 54 is provided with two sets of contacts 540and 54b. A final relay 56 is also provided in the circuit and isprovided with two sets of contacts 56:: and 56b. Relay 56 is wiredacross line 47 by a line 61 and is connected at its remaining terminalto the first set of contacts 54a. The contacts 54a are also connected tothe line 58 which is connected through contacts 480 or 52c to the line46. Thus closing of either set of contacts 43c or 520 will result in theactivation of relay 56 when the relay 54 has been actuated. The line 58is also connected directly to the first set of contacts points 56:!which are also wired to a line 60, connected to the time delay relay 51.The remaining terminal of time delay relay 51 is directly connee-ted tothe power line 47. Thus the first set of contacts 56a act as holdingpoints to complete the circuit of relay 51 regardless of the conditionof relay 54 after initial actuation thereof. The second set of contacts54b are holding contacts and are connected across the terminals ofswitch 42 to maintain the relay 54 in its actuated condition afterinitial closing of the switch 42. final contacts 56b are connectedbetween the power line 46 and the'line 59 which leads to the contacts48b and 52b.

The operation of this circuit is very simple. Assuming that a cant hasbeen cut with the remainder which is desired to be resawed, neithermanual switch 44 or 45 will be operated. As the board falls on thereceiving table 13, it will strike the plate 40 and thereby close theswitch 42. This closure will result in actuation of the solenoid 55 andcause the chains 23 to be lifted to thereby carry the board 9 to theabutment 30. When the board edge strikes the limit switch 43, thecircuit to the solenoid 55 will be broken and the cylinder assembly 28will return the chains 23 to their first positions. The lower board willthen strike the abutment 30 and the cant will ride over the abutment 30and be deposited by the gate 32 on the return conveyor 33. No otheroperation will result. The solenoid 55 will be held in its operationalposition during lateral movement of boards 9 by the closing of theholding contact points 54b. The closing of the contact points 54a willbe ineffectual, since they alone will not complete a power circuit.

Assuming first that the cant has been cut to a condition wherein theremaining portion of the cant is unusable, it is desirable that the gate32 be raised to the dashed line position illustrated in FIGURE 6. Thisis accomplished by closing the switch 44 during the time in which theboards 9 are being deposited on the table 13 by the delivery conveyor11. Closing of switch 44 results in the actuation of relay 48 and closesthe three sets of contacts 48a, 48b and 480. The circuit is held in acomplete condition by the holding contacts 48a. After the boards havebeen deposited on the receiving table 13 and the rear ends thereof havestruck the plate 40, the switch 42 will be closed as before. The lateralmovement of the board will proceed as described in the precedingparagraph, but closing of the relay contacts 54a will now result in thecompletion of the circuit to the relay 56. Thus the contacts 56a willinsure the completion of a circuit to the time delay relay -1 and at thesame time, the contacts 56a will complete a power circuit to thesolenoid 50 through the line 59 and contact points 48b. Thus the gate 32will be raised to the dashed line position illustrated in FIGURE 6,while the boards 9 are being carried toward the abutment 30. When theedge of the board strikes the limit switch 43, the circuit to thesolenoid 55 and relay 54 will be opened and the chains 23 will belowered as before. However, the circuit to relay 56 will remain in acomplete condition due to the action of the holding contacts 56a whichby-pass the contacts 54a. Thus the gate 32 will remain in its upperposition due to the continuance of power to the solenoid 5-0. Thiscircuit will remain completed until the time delay relay 51 opens thecontacts 51a. The relay 51 is a conventional component and may beadjusted to hold the circuit closed as long as desired. The opening ofcontact points 51a results in the activation of relay 48 and the openingof all of the circuits so as to preset the circuits for the next board.1

Should the final cut of the cant produce a split of two boards ofidentical desired thickness, the arms 35 should be raised to theposition illustrated in dashed lines in FIGURE 8. This is accomplishedin precisely the same manner as is the raising of the gate 32. Since thecircuitry for the solenoid 53 is identical to that associated with thesolenoid 50, no further description of its operation will be given.

Thus there is provided a completely automatic control circuit for themechanical separating mechanism described above. Obviously variouschanges could be made in both the mechanical and electrical componentswithout deviating from the intended scope of this invention. For thisreason the use of a double separating assembly is illustrated only as anexample. The assembly may be made as long as necessary to accommodatethe boards being cut by the resaw assembly. The addition of units alongthe receiving table 13 should be obvious.

Whether the cylinder assemblies are hydraulically 0perated orpneumatically operated is a matter of design choice. In mostinstallations the conveyor forms and directions will be varied from thatshown due to local conditions.

Equivalent changes are possible without changing the invention andtherefore the invention itself is to be limited only by the followingclaims.

Having thus described our invention, we claim:

1. A device for separating vertically stacked boards, comprising:

a fixed framework;

a delivery conveyor mounted on said framework adapted to conveyvertically stacked boards;

a receiving table located on said framework adjacent the delivery end ofsaid conveyor having an upper surface adapted to support boardsdeposited thereon by said delivery conveyor;

a plurality of lateral conveyors mounted on said framework perpendicularto the length of the boards deposited on said receiving table, saidlateral conveyors being conjointly mounted on said framework formovement between a first position wherein the top surfaces of saidlateral conveyors are located below the upper surface of said receivingtable to a second position wherein the top surfaces of said lateralconveyors are located above the upper surface of said receiving table;

a fixed abutment mounted on said framework adjacent one aligned end ofeach of said lateral conveyors toward which the top surfaces thereof aredirected and parallel to the lengthwise position of the boards depositedon said receiving table, the top edge of said abutment being locatedabove the top surfaces of said lateral conveyors when in said secondposition at a height less than the thickness of the lower board beingseparated;

means drivingly connected to said lateral conveyors adapted to propelvertically stacked boards supported on said lateral conveyors againstsaid abutment with force sufficient to cause boards resting on thelowermost board of each stack to slide therefrom over said abutment;

and longitudinally directed conveyor means mounted on said frameworkintermediate said lateral conveyors and directed perpendicularlythereto, the elevation of the top surface of said conveyor means beingintermediate the elevations of the top surfaces of said lateralconveyors at said first and second positions.

2. A device as defined in claim 1, further comprising:

actuating means mounted on said framework operatively connected to saidtransverse conveyors adapted to selectively effect movement of saidtransverse conveyors between said first and second positions;

first means located on said framework at the end of said receiving tableadjacent said delivery framework operatively connected to said actuatingmeans adapted, when activated, to cause said actuating means to movesaid transverse conveyors from said first position to said secondposition, said first means being engageable with boards on said deliverytable so as to be activated when the rear ends of the boards aredeposited on said table by said delivery conveyor;

and second means located on said framework adjacent said abutmentoperatively connected to said actuat ing means adapted, when activated,to cause said actuating means to move said transverse conveyors fromsaid second position to said first position, said second means beingengageable with boards on said transverse conveyors so as to beactivated when the boards have traversed the lengths of said transverseconveyors.

3. A device as defined in claim 1 wherein each of said lateral conveyorscomprises:

an inboard idler sprocket rotatably mounted on said framework about afirst common longitudinal axis;

an outboard driving sprocket rotatably mounted on said framework about asecond common longitudinal axis parallel to said first axis and locatedbelow said conveyor means;

an endless conveyor chain enmeshed about the inboard and outboardsprockets to thereby form a continuous loop, the top surface of saidchain on said sprockets being below the upper surface of said receivingtable and the total length of said chain being greater than the minimumloop necessary to encircle the two sprockets;

a supporting structure mounted on said framework intermediate saidinboard and outboard sprockets in transverse alignment therewith,including a horizontal plate on which said chain is supported;

linkage means connecting said supporting structure to said frameworkadapted to move said supporting structure from a first location whereinthe top surface of said chain is elevated below the upper surface ofsaid receiving table and a second location wherein the top surface ofsaid chain is elevated above the .upper surface of said receiving table.

4. A device for separating vertically stacked boards,

comprising:

a fixed supporting framework;

a delivery conveyor mounted on said framework adapted to conveyvertically stacked boards;

a horizontal receiving table located on said framework adjacent thedelivery end of said conveyor having an upper surface adapted to supportthe stacked boards deposited thereon by said conveyor;

a plurality of lateral chain conveyors mounted on said framework acrossthe lengths of stacked boards de posited on said table, each of saidconveyors includ pivot axis to an elevation above that of its pivot inga pair of sprockets mounted on said framework axis; for rotation aboutlaterally spaced parallel longitudiand control means operativelyconnecting said plate nal axes, a chain loosely enmeshed about said pairand said supporting frame of each lateral conveyor of sprockets in aclosed loop, and a vertically movadapted to raise said frames from theirfirst position able supporting frame mounted below the upper to theirsecond position responsive to downward mochain flight in supportingengagement therewith, said tion of said opposite edge of said plate.supporting frame being movable between a first posi- 6. The device asdefined in claim 4 further comprising: tion wherein the top surface ofthe chain supported a receiving conveyor on said framework spacedoutthereon is located below the upper surface of said Wardly of saidabutment; receiving table and a second position wherein the top amovable gate pivotally mounted on said framework surface of the chainsupported thereon is located adapted to occupy a first position whereinit bridges above the upper surface of said receiving table; the spaceseparating said abutment and said receiving a fixed abutment mounted onone framework adjacent conveyor and being adapted to be pivoted relativesaid aligned sprocket of each of said chain conveyors, to said frameworkto a second position thereby open-' said abutment extending the lengthof said receiving ing the space separating said abutment and saidretable and being located parallel to the position of the cciving table;stacked boards deposited thereon, the top edge of actuating means onsaid framework connected to said said abutment being located above thetop surfaces gate adapted to selectively pivot said gate from said ofsaid lateral conveyor chains when in said second first position to saidsecond position; position at a height less than the thickness of the andmanually operable control means operatively conlower board to beseparated; nected to said actuating means. common drive means connectedto said lateral con- 7. The device as defined in claim 4furthercomprising: veyors adapted to propel vertically stacked boards movablearms pivotally mounted on said framework supported on said lateralconveyors against said abutadjacent said abutment for motion abouthorizontal ment with force sufficient to cause boards resting ontransverse axes from a first position wherein said the lowermost boardof each stack to slide therefrom arms are entirely below the elevationof the top edge over said abutment; of said abutment to a secondposition wherein said and a longitudinally directed roller conveyormounted arms project upwardly above the top edge of said on saidframework with the rollers thereof interabutment; spersed between saidlateral conveyors in parallel actuating means on said frameworkoperatively conrelation thereto, the elevation of the top tangentialnected to said arms adapted to selectively move said horizontal surfacesof said rollers being intermediate arms from said first position to saidsecond position; the elevations of the top chain surfaces of saidlateral and maually operable control means operatively conconveyors atsaid first and second positions. nected to said actuating means. i

5. A device as defined in claim 4 wherein the support- 1% that of saidreceiving table, said plate being in the path of boards deposited onsaid receiving table by said delivery conveyor; means urging the edge ofsaid plate opposite to its References Cited in the file of this patentUNITED STATES PATENTS Brunner June 13, 1933 Horstkotte July 11, 1944 ingsurface of said delivery conveyor is elevated above said upper surfaceof said receiving table;

a hinged plate pivotally mounted on said receiving table about ahorizontal axis adjacent the delivery end of said delivery conveyor andat an elevation equal to

1. A DEVICE FOR SEPARATING VERTICALLY STACKED BOARDS, COMPRISING: AFIXED FRAMEWORK; A DELIVERY CONVEYOR MOUNTED ON SAID FRAMEWORK ADAPTEDTO CONVEY VERTICALLY STACKED BOARDS; A RECEIVING TABLE LOCATED ON SAIDFRAMEWORK ADJACENT THE DELIVERY END OF SAID CONVEYOR HAVING AN UPPERSURFACE ADAPTED TO SUPPORT BOARDS DEPOSITED THEREON BY SAID DELIVERYCONVEYOR; A PLURALITY OF LATERAL CONVEYORS MOUNTED ON SAID FRAMEWORKPERPENDICULAR TO THE LENGTH OF THE BOARDS DEPOSITED ON SAID RECEIVINGTABLE, SAID LATERAL CONVEYORS BEING CONJOINTLY MOUNTED ON SAID FRAMEWORKFOR MOVEMENT BETWEEN A FIRST POSITION WHEREIN THE TOP SURFACES OF SAIDLATERAL CONVEYORS ARE LOCATED BELOW THE UPPER SURFACE OF SAID RECEIVINGTABLE TO A SECOND POSITION WHEREIN THE TOP SURFACES OF SAID LATERALCONVEYORS ARE LOCATED ABOVE THE UPPER SURFACE OF SAID RECEIVING TABLE; AFIXED ABUTMENT MOUNTED ON SAID FRAMEWORK ADJACENT ONE ALIGNED END OFEACH OF SAID LATERAL CONVEYORS TOWARD WHICH THE TOP SURFACES THEREOF AREDIRECTED AND PARALLEL TO THE LENGTHWISE POSITION OF THE BOARDS DEPOSITEDON SAID RECEIVING TABLE, THE TOP EDGE OF SAID ABUTMENT BEING LOCATEDABOVE THE TOP SURFACES OF SAID LATERAL CONVEYORS WHEN IN SAID SECONDPOSITION AT A HEIGHT LESS THAN THE THICKNESS OF THE LOWER BOARD BEINGSEPARATED; MEANS DRIVINGLY CONNECTED TO SAID LATERAL CONVEYORS ADAPTEDTO PROPEL VERTICALLY STACKED BOARDS SUPPORTED ON SAID LATERAL CONVEYORSAGAINST SAID ABUTMENT WITH FORCE SUFFICIENT TO CAUSE BOARDS RESTING ONTHE LOWERMOST BOARD OF EACH STACK TO SLIDE THEREFROM OVER SAID ABUTMENT;AND LONGITUDINALLY DIRECTED CONVEYOR MEANS MOUNTED ON SAID FRAMEWORKINTERMEDIATE SAID LATERAL CONVEYORS AND DIRECTED PERPENDICULARLYTHERETO, THE ELEVATION OF THE TOP SURFACE OF SAID CONVEYOR MEANS BEINGINTERMEDIATE THE ELEVATIONS OF THE TOP SURFACES OF SAID LATERALCONVEYORS AT SAID FIRST AND SECOND POSITIONS.